CH3 by itself is not a complete compound. It's a methyl group, which is a functional group that acts as a substituent on a larger molecule.

Here's why it's not a complete compound:

* Valence: Carbon has four valence electrons. In CH3, carbon is only forming three bonds (one with each hydrogen atom). This leaves one valence electron unaccounted for, meaning the carbon atom is unstable.

* Stability: A complete molecule is generally considered stable and neutral. CH3 is highly reactive because of the missing bond and its open valence.

Examples of compounds containing the methyl group:

* Methane (CH4): This is the simplest alkane, where the methyl group is the entire molecule.

* Methanol (CH3OH): Here, the methyl group is attached to an oxygen atom and a hydrogen atom.

* Ethane (CH3CH3): Two methyl groups are bonded together.

To understand the name of a compound, you need to consider the entire structure, not just a fragment.